Metal-working machine



Jan. 20, A

l B, M. W. HANsoN METAL WORKING MACHINE' Filed June 15,I 1921 5 Sheets-Sheet l Jan'. 20, 1925.

- 1,523,958 B. M. w. HANsoN4 METAL WORKING MACHINE' Filed June 15. 1921 5 sheets-sheet 2v Jan, 20, l

B. M. W.`HANSON METAL WORKI NG MACHINE Filed June l5, 1921 5 Sheets-Shea?l 5 31a/manto@ Jan. 20, 1925 1,523,958

B. M. W. HANSON METAL WORKING MCIUN4 JJ! Filed June l5, 1921 5 Sheets-Shet 4 .am v A 91 9a r .afar4 attain/eq Jan; zo, 1925' B. M. W. HANSON METAL WORKING MACHINE Filed June 15. v1921 5 Sheets-'Sheet 6 Patented Jan. 20, 1925.

UNITED STATES BENGT M. W. HANSON, 0F HARTFORD, CONNECTICUT.

TvIETAL-WORKING- NIACHINE.

Application filed. June 15, 1921.

Y 1o all fw from t may concem.'

Be it known that I, BnNor M. WV. Hanson,

a citizen of the Unit ed States, and a resident of Hartford, county of Hartford, State of Connecticut, have invented certain new and useful Improvements in Metal-lVorking Machines, of which `the following is a speci [ication.

This invention relates to improvements in metal working machines. The various features of the present invention will be described with reference to their use in the particular machine now selected for the purpose of illustration which is a machine for centering work to be turned. I desire it to be clearly understood, however', that the present invention is susceptible of other embodiment and that the terms used are merely terms of description and not in any sense terms of limitation. It. will be obvious that many features of construction are sus ceptible of modification to suit different-re quirements, without departing from the spirit of the invention. t

The object of this invention is to provide a machine of the character described having various features of novelty and advantage, and which is particularly characterized by its accuracy and efficiency in operation.

In the accompanying drawings:

Fig. 1 is a side view of the complete machine.

Fig. 1fL is a detail view of the chuck operating lever. looking in the direction of arrow 1 in Fig. 1.

Fig. 2 is a` top view, partly in section, of the head stock.

Fig. 3 is a. side view of the head stock, a cover plate of the casing being removed.

Fig. +L is a central vertical sectional view taken longitudinally through the chuck spindle, that is substantially on line d-st of Fig. 2.

Fig. 5 is a front end view of the head stock, parts being shown in section.

Fig. G is a top plan view of the tail stock with a. cover plate removed, the operating lever which is carried by this cover, being shown in dotted lines, and parts being in section.

Fig. 7 vis a side view of the tail stock with parts broken away.

Fig. 8 is a front end view thereof with parts broken away. Fig. t) is a plan view of work holding lever 161 and associated parts.

Serial No. 477,860.

Fig. 10 is a detail view taken on line 10-10 of Fig. 8 and illustrates, in section, the forward end of one of the tool holders.

Fig. 11 is a detail sectional view taken on line 11-11 of Fig. 6 and illustrates the means for longitudinally adjusting the hand operated spindle of the work rest positioned on the tail stock.

Briefly, the machine disclosed in the present embodiment comprises a bed or base A on one end of which is fixed a head stock B provided with a chuck and means for appronimately positioning` one end of the work so that it may be readily gripped by the chuck; and on the other end of the bed is slidably mounted a tail stock C- provided with means for very accurately positioning and rotatably supporting the other end of the work relative tocertain tools carried by the tail stock. In the present instance, one of these tools comprises a combined drill and countersink and the other a shaving tool, and these tools are adapted to be successively brought into proper relation to the chuck, so that the drill may first form ahole in the work and then that hole may be trued up by the shaving.

rThe detailed construction of the head stock will now be described. Referring particularly to Figs. 4t and 5, mounted within suitable bearings 10 in the head stock casing 11 is a spindle 12 on the forward end of which is fixed a chuck having a head 13 in which is slidably mounted a pair of jaw blocks 14;, the jaws 15 of which aie stepped to accommodate pieces of work of different sizes. 16 designates a screw having left and right handed thread portions in threaded cngagement with the respective jaw blocks 1-1 so that when this screw is rotated the blocks move to and from each other to respectively chuck and unchuck, depending on the direction in which the screw is rotated. The screw 1G is rotatably supported at its ends by bearing members 17 which are preferablv in the form of screws to permit of such adjustment of the jaw blocks as to bring them concentric with the axis of the spindle 12. For the purpose of rotating the screw 16, it is provided with a pinion 18 with which meshes a rack 19 on a bar 22 extending through and slidably mounted in the spindle. This bar carries on its outer end a collar in the groove of which engages rollers 2st on the yoke end of an operating lever 2') pivoted as at 2G (Fig. 2). On the spindle 1Q is a lUO loose pulley 27 and alixed pulley.l 28,-to receive a belt 29 adapted to be" thrown from one of the pulleys to another by the shipper 30 carried by a rod 32 slidably mounted in suitable bearings in the casing ll. TheA shipper 30 is moved in direction `to throw the belt 29 from the loose pulley onto the lined pulley 28, through a bell crank 33and a connecting rod 34, by the foot treadle For convenience in operation of the machine, andf particularly forv the purpose of reducingA thenu'mber of movements necessary on the part of the operator, provision ishad'wlnre'by'f the chuck-may be unchucked and'thepower thrown oli' of the spindle simultaneously' byl the Y single-` operation ofl throwing the lever 25. Ther manner' in whichfthisis brought about willbeV most readily understood witl1referen`ce to Figs;

and'3. The' rod 32, together with the shipperV 30`carried-thereby, is normally urged in a directionl to th'row the beltonto the loose pulley 27 by a compression spring 3G. Pivoted within the headstock casing, as at 37 is a lever 38e-ne ofthe arms of'which carries a catch 39 with whichcooperates alatch- 42 having a slightv'ertic'al movementA in the collar 43 fixed to the rod 32. It? will be seen that when the shipper'is moved to throw the power on, the latch-42 will' have locking engagement with the catch 39 and hold the shipper in on position againstthe compresL sion of the spring 3G. Slidably mounted beneath the rod 32 is a rod 44 having a fixedA abutment 45 and a spring pressedlabutment 46 between which is interposed a projection or finger 47 depending'from the lever 38. Pivotally 'connected tothe rod 44 is arod 48 which extends through a-blvock 49 pi'votedias atv 52 to the lever 25. lVithin afbore in-the block 49 andengaging against-the rod 48 is a shoe 53`behind which is a compression spring 54. The force of this' spring is such that when the lever 25 is thrown the tendency is to longitudinally move the rod 48 andthe parts associated therewith.

Now,v assuming that the power is on v(in which case the latch 42 is cooperating with the catch 39), and also that the operating lever 25 isi'n the position shown in Figs. 2 and 3 (in which Case the chuck jaws are gripping` the work), when the lever is 'thrown to the right, the bar 22 will be dial is in registry with the mark 8l.

unchuck without throwing the power otl`, and therefore thefollowingmeans are provided for rendering the connection between the'lever 25 and the catch 39 inactive, at will. 57 designates a cam fixed to a stud 58 journalled in acover plate 59 and having at its outer end a handle 60 whereby it may be turned. The periphery of this cam has a flattened portion 61 and cooperates with an abutment 62 on the rod 44. lt will be seen that'when the flattened portion Gl faces the abutment 62, as shown in Fig. 3, the rod 4l will be moved when the lever is thrown in a direction to unchuck. lVhen-the caml is' turned to bring the circular portion thereof'against the abutment (2,\tbe rod 4i is held against reciprocation and the fric tion shoe 53 willanerely` slide along the rod 48 when the'lever 25 is thrown, and the beltA will not'beshifted.

Itisfurtherdesirable, in some instances. to throwL the power oil? without u'n'ch'ucking, and to this end there isprovided on the lever 38 a handle 64 extending through an opening-65 in the cover plate 59. The lever 38 may bemanually rocked by this handle to lower the catch 39 out of engagement with the latch 42 whereupon the spring 3G will throw the shipper 30 in a direction to shift the beltonto the loose pulley 27.

F or the purpose of supporting the work in such position that it maybe gripped by the chuck jaws, a work rest G8' and means for approximately adjusting the saine in accordance: with the diameter of the work, are provided, The work rest G8 comprises a rertically adjustable plate having a V at its upper end. Secured to the inner face of this plate is a T-block 69 guided by vertical ways 70 in the end 'plate 7l of the head stock casing. The inner face of the T-block (i9 carries a rack 72 within which cooperates a pinion 73on the inner'- end of a transverse or hand operated spindle 74 suitably supported in bearings on the nlate 71. Fixed on the outer end of this spindle 74 is a knob 75 and a disk 7G carrying a dial 77. This dial is suitably graduated in accordance with one or more systems ot nuasurements desired to be used. Secured to the head stock casing by means of screws 79 and partially covering the dial 77, is a plate 80 having an indicating mark or edge 8l. For the purpose of clamping the spindle 74 and. the rest in any position of adjustment, a screw 82 is provided which, when tightened up, tlexes the plate 80 and thereby clamps the peripheral flange 83 of the disk 7 (3 between the plate 8O and the head stock casing. lt will be understood that if the work to be engaged with the chuck is, for instance, two inches in' diameter, the spindle 74 will be turned until the corresponding indication on the The rest is now in such position that the pieces lill) of work can be successively positioned thereon for engagement with and disengagement from the chuck whether the latter is stationary or rotating.

The construction of the tail stock will now be described with reference to Figs. 6 to 11. The tail stock has a carriage provided with ways 91 which cooperate with ways 92 of the bed A. Mounted in this carriage is a horizontally disposed shaft 93 on which the legs 94 of a tool support 95 are journalled. Slidably mounted, side by side, in the support 95 are a pair of tool holders 96, 96. In the present instance, one of these tool holders carries a center drill 97 and the other a shaving tool 98. For the purpose of positioning the support 95 to bring the respective tools 97, 98 into operative position, set screws 99, 99 are provided on said faces of the support for cooperation with the respective stops 100, 100 on the carriage 90. 1t will be understood, in the present illustrative disclosure, when the support is in that station or position where the screw 99 engages the stop 100', the drill 97 is in alinement with the axis of the chuck and when the support is in its other angular station, the shaving tool is in such position as to true up the hole formed by the drill.

The holders 96, 96 are connected by links 103 to a lever 1041 pivoted as at 105 in a cover plate 106 of the support 95. It will be seen that when the lever is swung about its pivot, one of the holders is fed forwardly and the other one is sin'iultaneously withdrawn. The lever is also employed for rocking the tool support from one station to the other. For the purpose of preventing such rocking of the support, when either of the tools are in advance position and thus prevent injury thereto which might result from rocking the head before a tool was completely withdrawn frein the hole in the work, a plate 101 (see Figs. 6 and. 7) is provided on the carriage and this plate has a slot 102 through which the handle or level' 1041-. extends. The slot, intermediate its ends, has an offset portion and only when the lever 1011 is in alinement with this offset can the support be rocked.

As shown most clearly in Fig. 10, the tools are held within the bores 107 of the tool holders by means of set screws 108. Pivotally secured to the forward end of each holder, as by means of a screw 109, is a plate 110 having an opening 111 of, at least, the same diameter as that of the bore 107 and also a smaller tapered opening 112. When a piece of large size is to be operated upon, the opening 111 may be brought into registry with the bore 107 by turning the plate 110 on its pivot and the tool may eX- tend forwardly some distance beyond the plate 110 to take a deep cut into the work.

However, when the piece of work is of smaller diameter, it may be necessary to limit the extent to which the tool cuts into the work. To this end, the plate 110 is turned to the position shown in Fig. 10 from which view it will be seen that the opening 112 limits the extent to which the cutting point of the tool projects beyond the plate 110 and only to that extent can the tool be fed into the work.

For the purpose of preventing overheating of the tools during cutting, oil or other fluid is supplied to the tools in the following manner :"115 is an oil pump (see Fig. 1) from which leads a telescoping pipe 116, one end of which is carried by brackets 117 depending from the shaft 93 (see Figs. 7 and 8). This pipe communicates by means of passages 118 in one of the brackets 117 and the shaft 93 with a passage 119 in a leg 941 of the support 95. The passages 119, as shown most clearly in F ig. 6, communicate by means of ports 120 with a pair of bores 121 into which telescope tubular valves 122 fixed to the rear end of the holders 96. The tools 97, 98 are grooved as at 123 to allow for the flow of oil to the cutting edges thereof. It will be seen that with the arrangement just described when either of the tool holders is in advance position, the valve 122 connected to that holder does not cover its port 120 but the valve connected to the other holder blanks the other port 120, and thus the oil is conducted to that tool which is in cutting relation to the work and the flow of oil to the other holder is shut oil". It will be understood that the mere act of moving the tool holders in and out of operative position controls the flow of oil to the tools.

Reference will now be made to the means for accurately supporting the end of the work which is to be operated upon by the tools 97, 98. This means, in the present instance, includes a pair of work supporting rollers carried by slides 131 adjustaliily mounted in inclined grooves or openings 132 in a pla-te 133 connected to the forward end of the carriage90. rllhe carriage 90 including the plate 133 may be considered as the frame of the work rest. 134 designates a hand operated spindle having right and left hand screw threads in threaded engagement with traveling nuts or blocks 136 provided with inclined ribs 137 which engage in grooves 138 in the slides 131. It

will be seen that upon rotation of the spin dle 134 in one direction, 'the nuts 136 move towards each other and the ribs 137 acting' in the nature of wedges, cause the slides to move upwardly towards lthe axis on which the work is to be turned. llVhen the spindle 134 is rotated in the opposite direction, the nuts travel away from each other and lower the slides 131. Fixed to the forward end of the spindle 134 is a knob 142, the sleeve of `which vis provided-with a pinion 143 (see Fig. 6) meshing with the teeth 144 on the perimeter of a disk 145 carrying a` dial 146 similar to the .dial 77 heretofore described. The. disk 145 is journalled ona pin 147. The. plate 14S, which carries anindicating mark 149, is adapted to be flexed by the screw v to lock the disk and spindle 134 in adjusted positions. It will: be seen that when/the `spindle 134 is rotated to adjust the .rollers 130, v the extent oit :rotation will be indicated by thedial oriscale 146, and thus thework rest rollers may Abe Vvery accurately positioned in accordance with the diameter of the work so that when the work is placed Ion theseV adjusted rollers, itsaxis will bev in.

precise alinementavith the axis of thechuck and. in. -proper relation to the tools as they are ted `up to the work.

For the purpose of longitudinal-ly adjustingthe hand operated spindle 134, so that in lany lvertical position of yadjustment of the work .rest rollers these rollers will vbe symmetrically spaced `with respect to the axis, of the chuck,V the arrangement .shown most particularly in Fig. 11 is provided. As will be seen from this figure, a vpair of spaced collars 153 are .lined to the rear end of the spindle 134 and` between these collars is interposed a portion ot a member `154 mounted for adjustment in a recess 155 in the carriage 90. lCarried by the member 154 is a screwv 156-the head of .which abuts against a shoulder 157 on the carriage. Threaded into the carriage is a screw 158 the head of vwhich engages against an abutment 159 on the member 154. Now .if the spindle l134 is to be adj-usted to the right, referring to Fig. 11, the screw y156 is untightened and the screw 153 is screwed up until it has moved the member 154 and the spindle 134 to the proper extent, and then the screw 1156 is screwed home to hold the spindle 134 against, movement to the left. It it i`s necessary to adjust .thespindle 134 to the lei-t, the screw v:153 is untightened, the screw 156 is screwed further into the member 154 to draw the :same to the lett, and then the screw 153 is .tightened up.

For the purpose of securelyY holding `the work against vibration, while at the same time permitting ready positioning and removal of the work from the rest rollers 130, there is provided the work holding lever, shown most clearly in Figs. 3 and 9. The le`- rver 161 carries a roller 162 adapted .to rest uponthe top ot the work. This lever is `piv-` oted, as at 163, on the carriage 90, and concenti-'ically oi"- this pivot is a liXed disk 164 with the periphery of which Vcooperates a -friction. shoe 165 pivoted as at 166 to a block 167 which in turn is pivoted as at 168 to the lever 161. The pivots 'of the shoe 165 and the block 167 are so arranged that these members constitute a toggle joint. v169 designates a spring pressed plunger carried by the lever 161 and normally tending to turn the block 167 in a direction to engage the shoe with the disk 164. Slidably mounted. in the lever 161 and engaging at `one end against the block 167 is a pin 171. Pivoted to the 'tree end of the lever 161 a handle 1724 having a cam edge 173 for moving the pin` 171 towards the block 167 when the handle 172 is lifted. It will he understood that when the lever 161 is thrown down into operative position, the plunger 16S) will turn the block 167 in a direction to engage the shoe with the disk 164. The work cannot then raise the roller 162, for any torce tending -to .raise the lever 1:61l only wedges the shoe more tightly against the disk 164. then it is desired to raise the lever 16], to permit of` removal of the work, the handle is swung upwardly on its own pivot causing the cam ,edge 173, acting .through the'pin 171, to turn the block 167 in a direction to withdraw the shoe from the disk 164, and the lever is now free to be swung into the upright position shown in Fig. 6. The extent to which the lever can be thrown back is limited by the engagement of the projection 174 against the stop `17 The operation of the machine is @briefly `as follows. To set up vthe machine, the work rest 68 on the head stock is vertically adjusted to support one end of the work in approximate axial alinement with the chuck. The proper adjustment of the work rest .68 may, as stated, be determined by means of the scale 77. The work rest rollers 130. on the tail stock are very accurately adjusted by means of the hand operated spindle 134, in conjunction with the scale `146, so that when the work is positioned on these rollers it .will he in precise axial alinement with the chuck and 4in proper relation .with respect to the tools 97, 93. After the rests on the .hand and tail stock are thus adjusted, a piece of work is `placed. upon these rests; the lever f161 is lowered into the Aposition shown in Fig. 8.; and the operating lever is thrown to cause the chuck jaws to grip and rotate the work. The support=95 is moved into the angular station or position `where. the drill 97 Vis in alinement with the work and then the lever -144'is moved to feed the drill into t-he work. After .the drill has operated, it is withdrawn, :the support 95 is rockedto its other angular position `and .then the shavingitool is `fed into the work. After a center is thus formed in the `work,-the work holding lever l16,1.is raised into :the position shown in Fig. :6,.and the lever is thrown to move the shittingbar 22 in a direction Ito unchuck. Then the lever 25 is thus thrown to unchuclgthe shipper 30, in the event that the cam 57 is in the position shownin Fig. 3, is automaticaly released resulting in ltlt) throwing the power off. The piece of work may now be removed from the rests and the operation repeated on successive pieces.

I claim as my invention l. In a metal working machine, a head stock including a chuck, an adjustable work rest positioned forwardly of the chuck for supporting a piece of work to be gripped thereby, means for adjusting said work rest, a tail stock including a carriage, a tool carried by said tail stock for operation upon the end of the work, said tool having an operative position in axial alinement with the work, a work rest positioned on said carriage forwardly of said tool, and means for accurately adjusting saidV second mentioned rest to support the free end of the work in alinement with the tool.

2. In a metal working machine, work rotating means, a support mounted for angular movement about a fixed axis, a plurality of tool holders carried thereby, a tool carried by each holder, and means for positioning said support at a plurality of stations and at each of which a tool is in predetermined relation to the aXis of said work rotating means.

3. In a metal working machine, a rotating` chuck, a work rest for holding the work in axial alinement with said chuck, a support mounted for angular movement about an axis in parallelism with the axis of said chuck, a plurality of tool holders each supported for movement on a line parallel with the axis of said support, a tool carried by each tool holder and equally spaced from the axis of said support, means for angularly positicning said support to bring the several tools into predetermined relation to the axis of said chuck, and means for moving` said holders to feed the tools to the work.

'-l. In a metal working machine, a spindle, a chuck carried thereby, an operating lever therefor, mechanism for throwing the power ott of said spindle, and a connection between said lever and mechanism for releasing the latter when said lever is moved to unchuck, said connection including a longitudinally movable rod, a shoe carried by said lever and frictionally engaging said rod, and a spring behind said shoe.

In a metal working machine, a spindle, a chuck carried thereby, an operating lever therefor', an element for throwing the power on and ofi of said spindle, means normally urging said element into olf position, means for holding said element in on opposition, and a connection between said lever and last mentioned means for operating the latter to release said element and thereby throw the power oft' when the chuck is unchucked.

6. In a metal working machine, a spindle, a chuck carried thereby, means for operating said chuck, mechanism actuated by said operating means when the latter is moved to unchuck for throwing the power off of said spindle, and means for preventing, at will, actuation of said mechanism when said operating means is moved.

7. In a metal working machine, a spindle, a chuck carried thereby, an operating lever therefor, an element for throwing the power on and off of said spindle, a spring normally urging said element into olf position, a catch for holding` said element in on position, and a connection between said lever and said catch for releasing the latter when the lever is moved to unchuck.

8. In a met-al working machine, a spindle, a chuck carried thereby, an operating lever therefor, mechanism for throwing the power off of said spindle, a connection between said lever and said mechanism for releasing the latter when the lever is moved to unchuck, and means for rendering said con nection inoperative at will.

9. In a metal working machine, a spindle, a chuck carried thereby, an operating lever therefor, mechanism for throwing the power off of said spindle, a connection between said lever and mechanism for releasing the latter when said lever is moved to unchuck and including a longitudinally movable rod, and means for preventing, at will, actuation of said rod when said lever is moved to unchuck.

lO. In a metal working machine, a spindle, a chuck carried thereby, an operating lever therefor, an element for throwing the power off, a catch for holding said element in on position, a connection between said lever and catch for operating the latter to release said element when the lever is moved to unchuck, means for rendering said connection inoperative at will, and manually operable means independent of said lever for actuating said catch to release said element.

ll. In a metal working machine, a spindle, a chuck carried thereby, a shift-able bar for operating said chuck, a lever for shifting said bar, a belt shifter for throwing the power on and olf of said spindle, a spring normally urging said shifter into off position, a catch for holding said shifter in on position; a connection between said lever and catch including a longitudinal movable rod and a shoe carried by said lever and frictionally engaging said rod; a cam holding said rod against longitudinal movement, and means for actuating said catch to release said shifter independently of said lever.

l2. In a metal working machine, a snpport mounted for angular movement, a tool holder mounted for longitudinal movement therein, a lever pivoted to said support and operatively connected to said holder, and means cooperating with said lever for preventing rocking movement of said support lpelveeptwhen said lever is in zu predetermined position.

`.13.v-In a metal -Working machine, a support mounted fora-ngular movement-,a tool holder' i mounted for longitudinal. movement therein, .a lever 'pivoted to said support, a

f vconnection .bet-Ween Saidulever and holder,

Yport yand having ,a slot permitting jmovement of said leverbut preventing rook- 4Aing .otsa-id.` support except when saidlever and. a, plate iixed independently ot'vsaid suppivotal is Vin Withdrawn: position.

14. In a metal Working' machine, a oarrlage, a support` mounted for angular movev,ment therein, av pair of tool holders .slidably mountedin. 4Said support, ale-ver pivoted 4to said ,Supportwand operatively connected to Y said holders, and aplalte fixed, to said ear riagze andihaving a. slot through VWhie-lrusaid lever extends,` said slot being olfset intermediate its ends topermitvof rookingmovement of said.. support.

.15.111 af metal Working machine, ablase, a tail, stock .-adgnstably mounted ,thereon .and including a. oa:rr1age,.a support mounted for angular movement therein,.a .plurality of journalled onsaid sha-ft, a, pair ot tool ,holdyers arranged side by side 1n sa-i'd support, a

tool carried by each holder, interengaging means between said support and `tal-ringe andto each side of said support for angu! la-rly positioning the latter to bring the respect-ive tools into operative positioinnnd `a `Work arest on said carriage including means 'for adjusting the same.

17. In a metal yWorking machine, a tool holder having a bore, a. tool mounted in said bore, and aplate pivoted to the forwardI end of said tool holder and having` nn opening of `lesser diameter than said tool for limit-ing `the extent of projection ofsaid tool.

18.111 a metal Workingmaehine, a tool ,holder having a bore, a tool mounted for, adjust-ment in said bore, and auplute )ivoted `tothe `forward end of said tool holder and fhavingan opening of at least the same diameter as said tool sothat said tool may project vany desired ldistance beyond said platesaid vplate having-a second opening ol' lesserdiameter than said tool andada )ted to.- be brought into alinement with .snidfhore for limiting lthe extent of projection of the tool ,forwardly of the plate.

19. In a. `metal Working maehine, a support,.a pair of tool holders slidably 1nounted therein, a tool carried by eachv holder, means forr simultaneously lmoving said tool holders in opposite directions, passages .through said lholders for conducting a` fluid to said tools, and a. valve Carried by each holder, each ,of said valves beingin open position `when the tool holder with which it is :assoeiated is.advaneed and being in olosedgposition to shut oli' the flow of fluid 4when the tool holder,retracted.

BENGT `M. 1V. HANSON. 

